An Infrared Spectroscopic Study on the Hofmann-diam-type 1,9-Diaminononanemetal(II) Tetracyanonickelate(II)-Aromatic Guest Clathrates: M(H2N(CH2)9NH2)Ni(CN)4 ċG(M = Cd or Ni; G = Benzene, Naphthalene, Anthracene or Phenanthrene

IR spectra of M(1,9-Diaminononane)Ni(CN)₄G (M = Cd or Ni; G = benzene, naphthalene, anthracene or phenanthrene) are reported. The spectral data suggest that the host structures in these clathrates are similar to those of Hofmann-, -diaminoalkane type clathrates.     

Infrared Spectroscopic Study of the Hofmann-daon-Type Clathrates : M(1,8-diaminooctane)Ni(CN)4⋅G (M=Co, Ni or Cd; G=Aromatic Guest Molecules)

Infrared spectra of M(1,8-diaminooctane)Ni(CN)4G (M= Co, Ni or Cd; G=benzene, chlorobenzene, toluene, p-xylene, naphthalene or biphenyl) compounds are reported. The 1,8-diaminooctane molecules in the host permit the inclusion of bulky guest molecules. The spectral features suggest that the compounds are similar in structure to the Hofmann-type clathrates.     

An Infrared and Raman Spectroscopic Study of pn-Td-Type dl% -Propylenediaminemetal(II) Tetracyanometallate(II) Benzene Clathrates: M(dl-pn)M'(CN)4.nC6H6 (M = Mn, M' = Zn, Cd or Hg; M = Cd, M' = Cd or Hg; 1≤n≤1.5)

IR spectra of Mn(dl-propylenediamine)M(CN)4.nC6H6 (M = Zn, n = 1.25; M = Cd, n = 1.00 or M = Hg, n = 1.18), and IR and Raman spectra of Cd(dl-propylenediamine)M(CN) 4. 1.5C6H6 (M = Cd or Hg) are reported. The spectral data suggest that the former three compounds are similar in structure to the latter two pn-Td-type clathrates.     

Infrared spectroscopic studies of some piperidine metal(II) clathrates: M(C5H11N)2Ni(CN)4·G (M = Co,Ni; G = m-xylene,p-xylene or o-xylene; M = Ni; G = dioxane)

IR spectra of M(C₅H₁₁N)₂Ni(CN)₄·G (M=Co, Ni; G=o-, m- or p-xylene; M=Ni; G=dioxane) are reported. These clathrates are analogues to the previously reported classical Hofmann-type clathrates.     

An Infrared Spectroscopic Study of Pyrazine- and 4,4′-bipyridyl-Td-type Clathrates: Mn (pyrazine) M(CN)4 benzene (M = Cd or Hg) and Mn (4,4′-bipyridyl) M(CN)4. benzene (M = Zn, Cd or Hg)

The infrared spectra of the title compounds have been reported. The spectral data suggest that the host framework of these compounds are similar to those of the en-T_d-type clathrate compounds. There is good evidence for hydrogen bonding from ligand molecules to benzene molecules as a to hydrogen bond.     

Vibrational Spectroscopic Studies on the Td-Type Clathrates: M(trimethylenediamine)M'(CN)4⋅2C6H6 (M=Mn or Cd, M';=Cd or Hg)

IR spectra of Mn(C3H10N2)M(CN)42C6H6 (M=Cd or Hg),and IR and Raman spectra of Cd(C3H10N2)M(CN)4 2C6H6(M=Cd or Hg) are reported. The spectral data suggest that the former twocompounds are similar in structure to the latter two Td-type clathrates.     

Vibrational Spectroscopic Investigations of M(Imidazole)2Ni(CN)4·2 Dioxane Clathrates

Four new clathrates of the formula M(Im)2Ni(CN)4·2·Dioxane (where M = Co, Ni, Cu, Cd; Im = Imidazole) have been prepared in powder form and their FT-IR and laser-Raman spectra are reported for the first time. These clathrates are analogues to the previously reported classical Hofmann type clathrates except for the copper clathrate. The Cu clathrate has different spectral features in comparison with its analogues due to the Jahn-Teller effect.     

Electrophilic Substitution Mn(II) → M(II) (M = Co,Ni, Cu,Zn, Cd) in Gelatin-Immobilized Mn2[Fe(CN)6]

Reactions of electrophilic substitution Mn(II) M(II) (M = Co, Ni, Cu, Zn, Cd) are studied in gelatin-immobilized Mn(II) hexacyanoferrate(II) systems brought in contact with aqueous solutions of metal chlorides MCl₂. As the result of this contact, Mn(II) is replaced by Co(II), Ni(II), Cu(II), Zn(II), or Cd(II) to give heteronuclear metal hexacyanoferrates(II) (MHCF) of Mn(II) and two-charged ions. Neither of the systems under study showed a complete substitution of Mn(II) or the formation of the respective mononuclear hexacyanoferrate(II) M₂[Fe(CN)₆]. When any of the above gelatin-immobilized MHCF was brought in contact with an aqueous solution of MnCl₂, no electrophilic substitution M(II) Mn(II) was observed even for a long contact time.     

Electrophilic Substitution Co(II)→M(II) (M = Mn,Ni, Cu,Zn, Cd) in Co2[Fe(CN)6] Gelatin-Immobilized Matrices

Electrophilic substitutions Co(II) M(II) (M = Mn, Ni, Cu, Zn, Cd) in cobalt(II) hexacyanoferrate(II) gelatin-immobilized matrices in contact with aqueous solutions of corresponding chlorides MCl₂ were studied. As a result of this contact, Co(II) was shown to be replaced to some extent by Ni(II), Cu(II), Zn(II), or Cd(II) and to give heteronuclear cobalt(II) hexacyanoferrates(II) and two-charge ions. A complete substitution of Co(II) or the formation the respective mononuclear hexacyanoferrate(II) M₂[Fe(CN)₂] was observed in neither of the studied systems Co(II) M(II). No Co(II) Mn(II) substitution was observed, even though the immobilized matrix was in contact with a solution for a long time.     

Electrophilic Substitution Ni(II)→M(II) in Ni2[Fe(CN)6] Gelatin-immobilized Matrix Materials

The electrophilic substitution reactions Ni(II)M(II) (M = Co, Cu, Zn, Cd) occurring in nickel(II) hexacyanoferrate(II) gelatin-immobilized matrix materials on their contact with aqueous solutions of corresponding chlorides MCl2 were studied. During contact, Ni(II) is partly substituted by the other metal to form heteronuclear hexacyanoferrates(II) of nickel(II) and corresponding double-charged ions, and none of the studied reactions involves complete substitution of Ni(II) until the mononuclear hexacyanoferrate(II) M₂[Fe(CN)₆] has formed.     

NATURE OF SELENOCYANATE BONDING IN THE COMPLEXES OF MM'(NCSe)4 (M=Co,Ni, Zn,Cd; M′=Zn,Cd, Hg); WITH LEWIS BASES (PART II)

Abstract

Complexes of [MM′(NCSe)₄] (M=Co, Ni, Zn, Cd; M′=Zn, Cd, Hg;) with certain ligands (L), viz., ethylenediamine(en), isonicotinic acid hydrazide(inh), 3-aminopyridine(apy), pyridine(py), pyrazine 2-carboxamide(pza), pyrazine 2–3-dicarboxamide(pzd) and tetrahydrofuran(thf) have been synthesized and characterized. Their molar conductance, magnetic moments, infrared and electronic spectral studies indicate that these complexes are of three types: (i) cationic-anionic, viz., [ML₆] [M′(NCSe)₄] (M=Ni, M′=Cd, L=inh; M=Cd, M′=Hg, L=py; and M=Zn, M′=Cd, Hg; L=en;) (ii) monomeric bridged, viz., L₄ M(NCSe)₂ M′(SeCN)₂ (M=Co, Ni; M′=Cd, Hg; L=pzd;) (iii) polymeric bridged, viz., [dbnd](SeCN)₂ L₂ M(NCSe)₂ Hg (M=Co, Ni; M′=Zn, Cd, Hg; L=thf, pza and apy). The nature of bonding in these complexes has been related to the softness difference of M and M′ and the basicity of the ligands.     

Cyclohexylamine) 2 M(CN) 4 ⋅2C 6 H 6 (M = Cd or Hg)

Two new title compounds have been prepared in powder form. Their spectral data are found to be consistent with the structure foundin Hofmann-T_d-type clathrates.     

Spectroscopic properties of [M(CN)5py]n− complexes [M  Fe(II), Co(III); py = pyridine]

The IR, electronic and NMR spectra of K₂[Co(CN)₅py]·H₂O and Na₃[fe(CN)₅py]·3H₂O, as well as the Mössbauer spectrum of the latter complex, are reported and discussed. In particular it is argued that the wavenumbers and intensities of the i.r.-active CN stretching vibrations and the NMR chemical shifts of the m- and p-but not o-protons suggest greater metal to ligand back π-bonding in the Fe(II) complex than in the Co(III) complex.     

Vibrational spectroscopic study on some Hofmann-Td type clathrates: Ni(4-phenylpyridine)2M(CN)4·2G (M=Cd or Hg, G=1,4-dioxane)

New Hofmann-T(d) type clathrates in the form of Ni(4-Phpy)(2)M(CN)(4)·2G (where 4-Phpy=4-phenylpyridine, M=Cd or Hg and G=1,4-dioxane) have been prepared in powder form and their FT-IR and Raman spectra have been reported. The results suggest that these compounds are similar in structure to the Hofmann-T(d) type clathrates.     

SEMICONDUCTOR COPPER(II) MACROCYCLIC COMPLEXES. SYNTHESIS,CHARACTERIZATION AND ELECTRICAL PROPERTIES OF COPPER(II) COMPLEXES OF THE TYPE [Cu(TAABL)](NO3) · nH2O WITH L = NH(CH2)2NH2, NH(CH2)4NH2, NH(CH2)12NH2, AND THE COMPLEX [Cu(TAAB(C14H9N2O2)2)] · 4H2O

Abstract

The complexes [Cu(TAABNH(CH₂)₂NH₂)](NO₃) · 2H₂O, (1) [Cu(TAABNH(CH₂)₄NH₂)] (NO₃)·4H₂O, (2), [Cu(TAABNH(CH₂)₁₂NH₂](NO₃)·4H₂O,(3) and [Cu(TAAB(C₁₄H₁₀ N₂O₂)₂]·4H₂O, (4) have been synthesized and characterized by IR, mass spectroscopy, electronic spectroscopy, thermogravimetric analysis and elemental analysis. Electrical conductivity and activation energy evaluation were obtained from study of the temperature dependence of the electrical current (in tablet and thin film). Refraction and reflectance indices, absorption coefficient and optical activation energy were established through ellipsometry and UV-Vis spectroscopy. The electrical conductivity values at room temperature were within the range of semiconducting molecular solids (10^?6?10¹Ω^?1cm^?1).     

M(CN)(2) Species (M = Be, Mg, Ca, Sr, Ba): Cyanides, Nitriles, or Neither?

The "cyanide" salts of the group 2 (alkaline earth) metals exhibit remarkable structural variations: CN(-) binds to the metals via the carbon, via the nitrogen, and via bridged arrangements. The most stable geometries of the beryllium and the magnesium salts are linear (CNBeNC and NCMgCN, respectively), but CaC(2)N(2), SrC(2)N(2), and BaC(2)N(2) prefer twisted, bridged structures. However, several stationary points of the bridged complexes are close in energy, and considerable fluxionality is to be expected. These theoretical predictions (MP4SDTQ/6-311+G(2d)//MP2(fu)/6-31+G, Ca, Sr, Ba: 5s5p3d1f//5s5p3d basis sets and 10 valence electron pseudopotentials) invite experimental verification.     

Synthesis and Structure of Acetonitrile Solvates of Copper(II) Monofluoroacetate and Silver(I) Trifluoroacetate, [Cu2(CH2FCOO)4· 2CH3CN](CH3CN) and Ag3(CF3COO)3(CH3CN)2

Compounds [Cu₂(CH₂FCOO)₄· 2CH₃CN](CH₃CN) (I) and Ag₃(CF₃COO)₃(CH₃CN)₂(II) were synthesized and studied by X-ray structural analysis. Crystals Iare monoclinic, space group C2/c, a= 27.854(6), b= 8.286(2), c= 19.428(4) Å, = 106.82(3)°, V= 4292(2) ų, Z= 8, R ₁= 0.0426; crystals IIare triclinic, space group , a= 8.676(2), b= 9.819(2), c= 11.961(2) Å, = 95.27(3), = 109.59(3)°, = 104.60(3)°, V= 911.4(3) ų, Z= 2, R ₁= 0.0252. Structure Iis composed of the structural units (lanterns) typical of copper(II) carboxylates. The presence of an additional acetonitrile molecule noncoordinated by the copper atoms makes it possible to consider compound Ias a lattice clathrate. Structure IIhas no analogs among the silver carboxylates. It simultaneously contains silver atoms with coordination numbers varying from 2 to 4.     

Hexaaquacobalt(II) and hexaaquacadmium(II) 4-nitro-2,3,5,6-tetraoxopyridinates [M(H2O)6](C5HN2O6)2 · 2H2O (M = Co and Cd): Synthesis, structures, and properties

The complexes [Cd(H₂O)₆](C₅HN₂O₆)₂ · 2H₂O (I) and [Co(H₂O)₆](C₅HN₂O₆)₂ · 2H₂O (II) were obtained in the crystalline state by reactions of cobalt chloride and cadmium chloride with ammonium 4-nitro-2,3,5,6-tetraoxopyridinate, (NH₄)₂ · (C₅HO₆N₂)₂. Their cocrystallization gave the heterometallic complex [Cd_0.32Co_0.68(H₂O)₆](C₅HN₂O₆)₂ · 2H₂O (III). The crystal and molecular structures of complexes I-III were determined by X-ray diffraction. It was demonstrated that the complexation reactions occur by replacement of two ammonium cations 4-nitro-2,3,5,6-tetraoxopyridinate by the complex cations [M(H₂O)₆]²⁺. The tetraoxopyridinate anions and the complex cations are hydrogen-bonded through the coordinated and crystallization water molecules as well as through the O atoms of the organic anion. The thermolysis of complexes I and II was examined by TGA.     

Ion-Exchange Processes M(II) → Fe(III) and Fe(III) → M(II) in Metal Hexacyanoferrate(II) Gelatin-Immobilized Matrices (M = Mn,Co, Ni,Cu, Zn,Cd)

Ion-exchange reactions M²⁺ Fe³⁺ and Fe³⁺ M²⁺ (M = Mn, Co, Ni, Cu, Zn, Cd) were studied in metal(II) hexacyanoferrate(II) gelatin-immobilized matrices M₂[Fe(CN)₆] in contact with aqueous FeCl₃ solutions and Fe₄[Fe(CN)₆]₃ in contact with aqueous MCl₂ solutions. It was shown that in both cases, M²⁺ was replaced by Fe³⁺ and Fe³⁺ was replaced by M²⁺ to some extent, but no complete replacement was observed in the M₂[Fe(CN)₆]–FeCl₃ or Fe₄[Fe(CN)₆]₃–MCl₂ systems under study. No electrophilic substitution Fe³⁺ Mn²⁺ was found to occur in any noticeable degree during the contact of Fe₄[Fe(CN)₆]₃ with aqueous MnCl₂ solutions even when this contact occurred for 1 h and longer.     

Hexanuclear Fe(III)2Co(III)2M(II)2 (M = Cu, Ni, Mn) clusters based on Kläui's tripodal ligand and tricyanometalates: syntheses, structures and magnetic properties

With the use of Kl?ui's tripodal ligand, [(Cp)Co(P(O)(OEt)(2))(3)](-) (L(CoEt), Cp = cyclopentadiene) as the auxiliary ligand to react with different metal salts and tricyanometalate building blocks, five neutral trimetallic hexanuclear complexes: [(Tp)(2)Fe(2)(CN)(6)Cu(2)(L(CoEt))(2)]·6H(2)O (1, Tp = hydridotris(pyrazolyl)borate), [(Tp*)(2)Fe(2)(CN)(6)Cu(2)(L(CoEt))(2)]·2H(2)O (2, Tp* = hydridotris(3,5-dimethyl-pyrazolyl)borate), [(pzTp)(2)Fe(2)(CN)(6)Cu(2)(L(CoEt))(2)]·H(2)O·3MeOH (3, pzTp = tetra(pyrazolyl)borate), [(Tp)(2)Fe(2)(CN)(6)Ni(2)(L(CoEt))(2)(MeCN)(2)]·2MeCN·2H(2)O (4) and [(Tp)(2)Fe(2)(CN)(6)Mn(2)(L(CoEt))(2)(MeCN)(2)]·2MeCN (5), have been obtained and structurally characterized. Magnetic measurements confirm that there are ferromagnetic couplings between the cyano-bridged Fe and Cu/or Ni ions and antiferromagnetic interaction between the cyano-bridged Fe and Mn ions. Slow relaxation of the magnetization is observed in complexes 1 and 4, while complex 3 exhibits metamagnetic behavior with a critical field of 17.5 kOe.